High-density magnetomyography with optical magnetometers reveals spatiotemporal patterns of evoked muscle activity

High-density magnetomyography with optical magnetometers reveals spatiotemporal patterns of evoked muscle activity | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article High-density magnetomyography with optical magnetometers reveals spatiotemporal patterns of evoked muscle activity Simon Nordenström, Victor Lebedev, Stefan Hartwig, Marlen Kruse, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8593347/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Magnetomyography (MMG) holds great potential as a contactless alternative to electromyography (EMG). However, the spatiotemporal dynamics of the myomagnetic field in vivo remain largely unknown, limiting signal interpretability and hence the use of MMG. Here, the myomagnetic field of the abductor digiti minimi muscle is measured in vivo at 69-by-2 effective positions by scanning a grid of six triaxial optically pumped magnetometers (OPMs) along the muscle, while reproducible muscle contractions are evoked electrically. In this way, the compound muscle action field (CMAF) is measured with high density (1 mm sampling steps) and its evolution is referenced to the underlying anatomy based on 3D scans and magnetic resonance images. A model is used to simulate the expected signals. It suggests that the clinically relevant innervation zone (IZ) manifests as a zero-crossing of the azimuthal CMAF component. Based on this, contactless IZ localization is demonstrated in three subjects by projecting the zero-crossing onto the skin. The estimated IZ localizations deviate by 1.7 mm to 4.1 mm from estimates with simultaneously recorded 64-channel surface EMG. With the first millimeter-scale spatiotemporal mapping of magnetic muscle activity in vivo, this study paves the way for the use of MMG in biomedical applications. Medical Physics Magnetomyography spatial scanning HD-MMG HD-sEMG innervation zone spatiotemporal maps optically pumped magnetometer quantum sensors Full Text Additional Declarations The authors declare no competing interests. Supplementary Files SupplementaryFigures.docx Supplementary Figures. SupplementaryVideoV1.mp4 Supplementary Video. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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